ABS

1994 Cadillac El Dorado • V8 2WD Automatic • 152,000 miles

I have a 94 cadillac eldorado. When the ABS light is on, I can drive the car but the traction is dis engaged. When the ABS light is off, the traction is engaged or active, causing the rear passenger side wheel is drag, and grind. What could be wrong? Is the sensor located on the wheel hub? Or can I turn off the traction control from the dash board?